A novel endoscopic classification for craniopharyngioma based on its origin

Abstract

Endoscopic endonasal approach for craniopharyngioma (CP) resection provides a wide view and direct observation of hypothalamus and origin of tumor. Under endoscopy, 92 CPs were classified into 2 types: Peripheral and Central, according to its relation to pituitary stalk. Peripheral type was further divided into 3 subtypes: Hypothalamic stalk, Suprasellar stalk and Intrasellar stalk CP, according to the different origin site along hypothalamus-pituitary axis. Peripheral type arisen from the stalk but expanded and grown laterally in an exophytic pattern, accounting for 71.7% of all CPs, preservation rate of stalk was higher (76.0%). Central type grew within and along pituitary stalk and located strictly in the midline. The pituitary stalk was hardly preserved (only15.4%). Hypothalamic stalk CPs (n = 36, 54.6%) developed from the junction of hypothalamus and stalk, hypothalamus damage was found in all of this subtype after surgery. Suprasellar stalk CPs (n = 14, 21.2%) originated from the lower portion of stalk and displaced hypothalamus upward rather than infiltrated it. Intrasellar stalk CPs (n = 16, 24.2%) arose from the subdiaphragma portion of the stalk, with less hypothalamus damage. Recoginzing the origin of CP is helpful to understand its growth pattern and relation to hypothalamus, which is critical in planning the most appropriate surgical approach and degree of excision.

Craniopharyngiomas in Children - Experience of Consecutive 152 Operated Cases

“…The new endoscopic CPH classification emphasizes the origin of the tumour independently of the recognition pituitary stalk and helps determine the extent of hypothalamus injury prior to surgery. CPH were classified as central or peripheral, the latter one being further classified as hypothalamic stalk CPH, suprasellar stalk CPH or intrasellar stalk CPH (34). Regarding the extent of the surgery, TS shows a higher rate of complete removal as a primary treatment and also in the recurrent cases (85% and 53%) when compared to TC approach (45% and 21%) (35).…”

Craniopharyngiomas: An Appropriate Surgical Treatment based on Topographical and Pathological Concepts

“…Topographical classifications considering two axes: one vertical or lateral and one horizontal. Five CP classifications are based on the vertical and antero-posterior axes [37,38,44,55,56,60,61], and two schemes consider the lateral position of the tumor relative to the pituitary stalk in addition to either an antero-posterior axis [68,69] or a vertical axis [58]. For example, William H. Sweet (1910Sweet ( -2001, who advocated the pterional-trans-lamina terminalis route for CPs, proposed a scheme based on the tumor position relative to the optic chiasm and 3V.…”

“…For example, William H. Sweet (1910Sweet ( -2001, who advocated the pterional-trans-lamina terminalis route for CPs, proposed a scheme based on the tumor position relative to the optic chiasm and 3V. Very recently, Amin K. Kassam [55] and Bin Tang [58], two experts in the endoscopic extended transsphenoidal approach, used the pituitary stalk and infundibulum as the structures of reference to define CP topography, due to the fact that they are the first ones identified when using the transsphenoidal route. Specifically, Kassam's scheme considers four major CP types *55+: i) preinfundibular CPs, or lesions located in front of the stalk-infundibulum complex, just behind the optic chiasm; ii) transinfundibular CPs, tumors expanding into the pituitary stalk itself; iii) retroinfundibular CPs, corresponding to those lesions growing behind the stalk-infundibulum complex which can expand either into the 3V cavity or towards the suprasellar-interpeduncular compartments; and iv) intraventricular CPs, situated above an intact pituitary stalk.…”

“…Therefore, an essential aspect of CP surgical planning is to decide "where to begin". The optimal surgical route is that which provides a direct and broad view of the tumor-brain cleavage plane, particularly of the expected areas of maximal adhesion to the hypothalamus [1,33,42,49,55,58,84].…”

“…In the last ten years, the use of endoscopic endonasal transsphenoidal routes to remove CPs has been expanding [55,57,58]. The major advantage of this route is that it fully exposes the tumor-hypothalamus adhesion plane present in tumors developing within the infundibulum (infundibulo-tuberal CPs) and in suprasellar lesions invading the 3V (secondary-intraventricular CPs).…”